Journal of Dental Medicine

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This study is aimed to evaluate the effect of covering exposed root surface by collagen membrane and to compare this method with coronoally advanced flap covering. 26 teeth in 20 patients (12m/8f) with Miller1 gingival recession were selected. 14 teeth were allocated into test group and 12 teeth in control group. Following first phase of treatment, clinical parameters including the height and width of gingival recession, attachment height, gingival crevice depth and keratinized tissue width were measured. In test group, coronally advanced flap was prepared and gingistat (as space maintainer) and collagen membrane was applied. For control group, coronally advanced flap method was applied without any further action. The measurements were done in 1,2 and 3 months post surgery. In test group, the reported root coverage was 71% while in control group was 57% which represents statistically significant difference. From first to third month post surgically, the average gingival recession in test group was 0.21 mm which was considered as creeping attachment phenomenon while in control group gingival height was increased 0.14 mm. the average width of recession and crevice depth decrease was not significantly different between the groups. On the other hand, The average attachment gain and keratinized tissue increase was significantly varied among the groups. In general, it can be concluded that application of collagen membrane as well as gingastat space maintainer can bring about satisfactory results in covering exposed root surfaces.

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Background and Aims: Today, use of adhesive systems is the most common materials in restorative dental procedures. The aim of this study was to evaluate the effect of different air-drying periods on the microtensile bond strength of composite to dentin using adhesive.

Materials and Methods: 15 sound molar teeth were selected. The an occlusal surfaces of teeth were removed with silicon carbide disks (3M/USA) to reach flat surface of dentin. Then according to the air drying of solvent, the teeth were divided to five groups. After 5 sec etching and rinsing for 15 sec , the teeth were air dried for 3 sec . Then Singlebond (3M) was used with different air-drying times (0s, 2s, 5s, 10s, 30s) and cured. Then after insertion and curing of Saremco (microhybrid low shrinkage/Switzerland) composite, the teeth were thermocycled for 500 cycles. Then hour glass slabs with 1 mm² interface was created. Specimens were then subjected to µTBS force until fracture. Data were analyzed using ANOVA and Bonferroni tests.

Results: Statistical tests showed that there were significant differences between bond strength of groups (P=0.002). The mean of µTBS for the 2 Sec and 30 Sec evaporating time was the most and the least vawes, respectively.

Conclusion: An optimum air-drying time for solvent evaporation was the lowest time recommended by the manufacturer. Over and under evaporation time decreased µTBS significantly.

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  Background and Aims: The purpose of the present study was to review the studies regarding serological and salivary oxidant / antioxidant status in patients with recurrent aphthous stomatitis (RAS).

  Materials and Methods: The literature was searched using key words RAS, Antioxidants, Saliva, Hematinic (s) and Hematinic Acid in the last 10 years, particularly the recent 3 years (2010-2013). At total of 37 clinical trials, 18 case-control articles were selected and evaluated fulfilling the requirements as the RAS patients having at least 3 oral aphthous attack per year. The exclusion criteria included systemic as well as periodontal diseases, iron deficiency associated anemia, medication usage and smoking.

  Conclusion: Almost all lipid-peroxidation studies in serum and saliva were manifested by an increase of malondialdehyde (MDA) concentration in RAS patients compared with controls. This would indicate the role of reactive oxygen species (ROS) in the etiology of the disease. Serum trace elements (Zn, Se) were reduced and Cu was increased in RAS patients in comparison with control individuals. A decreased serum superoxide dismutase (SOD) and an increased salivary SOD were observed in all RAS patients. Catalase (CAT) and uric acid (UA) analyses were non-inclusive. Levels of paraoxonase and arylesterase as well as antioxidant vitamins (A, E, C) were lower in RAS patients than that of controls.

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  Background and Aims: To ensure root canal treatment success, endodontic microbiota should be efficiently reduced. Several irrigation devices have been recently introduced with the main objective of improving root canal disinfection.The purpose of this study was to evaluate the rinsing effect of RinsEndo system in reduction of enterococcus faecalis in comparison with conventional hand syringe in infected root canals.

  Materials and Methods: 60 extracted single canal anterior teeth were infected with enterococcus faecalis and divided into 3 groups: RinsEndo system, conventional hand syringe and control group. The enterococcus faecalis colonies were counted in each group before and after rinsing. Data were analyzed using Variance and Kruskal Wallis test.

  Results: The mean of enterococcus faecalis growth after rinsing was 3.50×10³ in group with conventional syring rinsing, 2.04×10³ in group with RinsEndo washing and 6.11×10³ in control group. Reduction of enterococcus faecalis after rinsing was statistically significant in each group (P<0.001). The amount of reduction in number of colonies with RinsEndo and conventional syringe rinsing was higher in comparison with control group and this difference was significant (P<0.001). RinsEndo rinsing effect was statistically significantly higher in comparison to conventional syringe as well (P<0.001).

  Conclusion: Rinsing with RinsEndo system was significantly more efficient in reduction of enterococcus faecalis from root canal in comparison with hand syringe washing.

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Background and Aims: Soy milk in competition with other drinks introduced as healthy and nutrient drink. Nowadays, most important tendency to consume soy milk is new extended developments to produce soy milk with more acceptable taste and is believed that soy milk is a good substitute for bovine milk in lactose-intolerant people. Cariogenic potential of bovine and soy milk is a subject for lots of researches in the last decade. The aim of this study was to evaluate the effect of soy and bovine milks on the pH changes of dental plaque.

Materials and Methods: In this study, 10 healthy dental students in age range of 25-35 were selected after written consent upon study entrance criteria's such as, amount of saliva streptococcus mutans, amount of lactobacillus, salivary secretion rate, buffering capacity of saliva, absence of active dental caries, absence of systemic disease and etc. Dental plaque pH in the interproximal areas of 2nd premolar and 1st molar in all 4 quadrants was taken by Metrohm micro electrode and digital pH meter before (0) and at 2, 5, 7, 10, 15, 20, 30, 40, 50 and 60 min after taking with 3 tested materials (soy milk, plain milk 1.5% and 10% sucrose solution as a positive control). Then pH curves were drawn according to the time of each test product. In this study, using pH=6 was considered as critical pH. Maximum pH drop and ∆pH after taking 3 tested materials were analysed Repeated measure ANOVA (P<0.05).

Results: According to the test materials, the lowest pH was after rinsing with 10% sucrose solution following soy milk and in the last was 1.5% bovine milk. All the test materials showed significant differences among each others
(P<0.05).

Conclusion: Bovine milk in none of frequent timing dropped its pH below basic pH but also significantly increased the plaque pH above the critical pH. The maximum pH drop for soy milk was in 2minutes after consumption but it never reached below the critical pH.